The present invention relates to agents for coloring keratin fibers which comprise special m-phenylenediamine derivatives, to a method of coloring hair using these agents, and to some of these m-phenylenediamine derivatives themselves and intermediates which are formed during the preparation of these compounds.
For the coloring of keratin fibers, in particular human hair, so-called oxidation colorants play a preferred role due to their intense colors and good fastness properties. Such colorants comprise oxidation dye precursors, so-called developer components and coupler components. The developer components form the actual dyes under the influence of oxidizing agents or of atmospheric oxygen with one another or with coupling with one or more coupler components.
The developer components used are usually primary aromatic amines with a further free or substituted hydroxyl or amino group located in the para or ortho position, diaminopyridine derivatives, heterocyclic hydrazones, 4-aminopyrazolone derivatives, and 2,4,5,6-tetraminopyrimidine and derivatives thereof.
Examples of developer components include, but are not limited to, p-phenylenediamine, p-tolylenediamine, 2,4,5,6-tetraminopyrimidine, p-aminophenol, N,N-bis(2-hydroxyethyl)-p-phenylenediamine, 2-(2,5-diaminophenyl)ethanol, 2-(2,5-diaminophenoxy)ethanol, 1-phenyl-3-carboxamido-4-aminpyrazol-5-one, 4-amino-3-methylphenol, 2-aminomethyl-4-aminophenol, 2-hydroxy-4,5,6-triaminopyrimidine, 2,4-dihydroxy-5,6-diaminopyrimidine, 2,5,6-triamino-4-hydroxypyrimidine and 1,3-N,N′-bis(2-hydroxyethyl)-N,N′-bis(4-aminophenyl)diaminopropan-2-ol.
Typical coupler components include, but are not limited to, m-phenylenediamine derivatives, naphthols, resorcinol and resorcinol derivatives, pyrazolones and m-aminophenols. Suitable coupler substances are, in particular, 1-naphthol, 1,5-, 2,7- and 1,7-dihydroxynaphthalene, 5-amino-2-methylphenol, m-aminophenol, resorcinol, resorcinol monomethyl ether, m-phenylenediamine, 1-phenyl-3-methylpyrazol-5-one, 2,4-dichloro-3-aminophenol, 1,3-bis(2,4-diaminophenoxy)propane, 2-chlororesorcinol, 4-chlororesorcinol, 2-chloro-6-methyl-3-aminophenol, 2-methylresorcinol, 5-methylresorcinol and 2-methyl-4-chloro-5-aminophenol.
Good oxidation dye precursors should firstly satisfy the following prerequisites: during oxidative coupling, they must form the desired shades in an adequate intensity and fastness. They must also have a good ability to attach to the fibers and particularly for human hair there should be no notable differences between stressed and freshly grown hair (equalizing ability). They should be resistant to light, heat, perspiration, rubbing and the effect of chemical reducing agents, e.g. permanent waving liquids. Finally, if used as hair colorants, they should not color the scalp excessively, and in particular they should be acceptable from a toxicological and dermatological point of view. In addition, it should be possible to readily remove the coloration achieved from the hair again by bleaching if it does not correspond to the individual wishes of the individual person and is to be reversed.
Using a developer component or a special coupler/developer combination on its own it is generally not possible to obtain a shade which looks natural on the hair. In practice, therefore, use is usually made of combinations of different developer and/or coupler components. There is therefore a continuing need for novel improved dye components which are also unproblematic from a toxicological and dermatological point of view.
It was therefore one object of the present invention to develop novel coupler components which satisfy the requirements placed on oxidation dye precursors, especially with regard to the toxicological and dermatological properties, and permit colorations in a broad color spectrum with good fastness properties.